1. The Field of the Invention
The present invention relates to the identification, capture and analysis of data transmitted over a communications system. More specifically, embodiments of the present invention are concerned with the definition and use of a virtual protocol analyzer.
2. Related Technology
Many data communications systems use a variety of different data transmission mechanisms to enable communication between and among associated subsystems. In general, the type of data transmission mechanism employed in a given situation is determined with reference to the particular tasks desired to be accomplished in connection with that transmission mechanism and associated systems. Each different transmission mechanism, in turn, is associated with a particular transmission, or communication, protocol that defines various parameters concerning the transmission of data in connection with the transmission mechanism. Such communication protocols commonly specify, for example, the manner in which data is encoded onto a transmission signal, the particular physical transmission media to be used with the transmission mechanism, link layers and other attributes.
As suggested above, a single data communications system may use multiple different transmission mechanisms and protocols. As an example, an enterprise may employ a communications system that uses five different data communication protocols, each adapted for a particular situation, wherein the five protocols may include: a first protocol for a high speed, inexpensive short-haul connection on the computer motherboard; a second high-bandwidth protocol for data center transmissions; a third protocol that is suited for efficiently transmitting information across the enterprise local area network (“LAN”); a fourth protocol adapted for high bandwidth, long haul applications; and, finally, a fifth communication protocol suited for data transmission to high performance disk drive storage systems. Thus, the typical communications system comprises a patchwork of different subsystems and associated communications protocols.
In this way, a communications system can be created that makes maximum and efficient use of the functionalities and capabilities associated with various different communications protocols. Further, advances in communications technology, coupled with declining costs, enable such communications systems to be implemented in a relatively cost effective fashion.
While communications systems that include components, devices and subsystems of varying protocols are able to exploit the respective strengths and useful features associated with each of the protocols, such multiple protocol systems can be problematic in practice. This is especially true where problem identification, analysis and resolution are concerned. In particular, the use of multiple communications protocols within the bounds of a single communications system greatly complicates the performance of such processes.
For example, as network data moves from a point of origin to a destination, by way of communication links, or simply “links,” the data passes through a variety of devices collectively representing multiple protocols. Typically, each such device modifies the network data so that the data can be transmitted by way of a particular link. However, modification of the data in this way often causes errors or other problems with the data. Such errors may occur as the result of various other processes and conditions as well. Thus, the various communication links in a communications system are particularly prone to introduce, or contribute to the introduction of, data errors. Moreover, data errors and other problems present at one location in the data stream may cause errors or other problems to occur at other locations in the data stream and/or at other points in the communications system and associated links.
One approach to problem identification, analysis and resolution in communications systems involves capturing a portion of the network data traffic. The captured data can then be retrieved for review and analysis. In some cases, such data capture is performed in connection with a protocol analyzer that includes various hardware and software elements configured and arranged to capture data from one or more communications links in the communications system, and to present the captured data by way of a graphical user interface.
Generally, such protocol analyzers, or simply “analyzers,” capture data traffic in the communications system over a defined period of time, or in connection with the occurrence of predefined events. Use of the analyzer thus allows a network administrator to track the progress of selected data as that data moves across the various links in the communications system. Corrupted or altered data can then be identified and traced to the problem link(s), or other parts of the communications system. As discussed below, such protocol analyzers can provide useful results, but it is often the case that employment of typical protocol analyzers imposes unacceptable costs in terms of communications system performance and down time.
A typical protocol analyzer includes two or more ports configured and arranged to capture data on a communications link of a communications system. For high speed serial networks, two ports are needed to capture data on a bi-directional communications link. The two ports are sometimes referred to as a “port pair.” Typically, the user connects the ports in-line with the communications link and then sets up triggering criteria to be used as a basis for the capture of data passing through the communications link.
In some cases, protocol analyzers may have as many as 64 ports capable of capturing data, and the protocol analyzer may be capable of capturing data conforming with any of a variety of communications protocols. Typically, the ports of protocol analyzers have a native communications protocol, which corresponds to the data that the analyzer port is designed to monitor and capture. Examples of such protocols are Gigabit Ethernet, Fibre Channel, and Infiniband. The ports in such protocol analyzers can be configured in a variety of ways. For example, the ports in the aforementioned 64 port protocol analyzer can be combined to create a single instrument having 32 port pairs. Alternatively, the ports can be configured into 32 different port pair instruments for use by 32 different users.
A significant problem with typical protocol analyzers however, is that if a network administrator or other user wishes to instrument a communications link for data capture and/or evaluation, the communications link must be broken and reconnected with the protocol analyzer. This is problematic at least because the process of breaking links significantly disrupts the operation of the communications system and increases communications system down time. The fact that users of conventional protocol analyzers are often required to break multiple communication links each time a different set of links is to be monitored further aggravates this problem.
In view of the foregoing, and other, problems in the art, what is needed are systems and methods for enabling a user to define and implement multiple virtual protocol analyzers, each of which may include a different combination of ports, within a single device. Such systems and methods should also allow the user to readily reconfigure a virtual protocol analyzer. Finally, exemplary embodiments of the invention should contribute to a relative reduction in the need to break communication links once the communication links have been initially instrumented.